LOUISVILLE — With a run of exquisite command and mastery given a capable and chaotic field of 20 colts, veritable greenhorn Justify won the 144th Kentucky Derby on Saturday evening on a track officially marked sloppy but closer to deluged. He granted a sight that looked very much like greatness and cemented himself as a star after snaring the lead with a half-mile left and keeping it from there. He also used his nimble hoofs and considerable strides to rewrite a couple of rigid sentences and charts in the Derby’s monumental record book.

The son of the late Scat Daddy and mare Stage Magic from Glennwood Farm in Versailles, Ky., Justify became the first horse in 136 years to win the Derby after not having raced as a 2-year-old, following at long, long, long last upon the 1882 surprise winner, Apollo. He made his trainer, Bob Baffert, only the second to coax at least five Kentucky Derby winners, inching Baffert past D. Wayne Lukas and Herbert “Henry” Thompson and into second place alone, one shy of Ben A. Jones and the six he collected between 1938 and 1952.

And when Justify made sure the stretch charges of Good Magic from the outside and Audible from the rail lacked the mustard to reach his flank or catch his eye, then defeated Good Magic by 2½ lengths with Audible another head behind, he had Derby savants placing him among the most accomplished of the 144 champions.

“I just keep using this word, I don’t know why, but he’s so above-average,” said Mike Smith, who at 52 became the second-oldest jockey to win the Kentucky Derby.

“He’s a superior horse,” Baffert said.

“He’s so athletic,” Smith said. “He gets over the ground so easy. He’s able just to keep running.”

All of the above meant that after some palpitations over some harrowing early fractions of 22.24 and 45.77 seconds, Baffert spent the last 100 yards of the race in another state: awe.

“I knew that last eighth, he was going to win, and I was just in awe of the performance,” he said. “I mean, that’s the best Kentucky Derby-winning performance that I’ve brought up here. He just put himself up there with the greats.”

Off as the 5-2 favorite and free from the gate sans trouble to match the jockey and trainer’s fondest wish, Justify hurriedly found himself on the cusp of the lead, next to the anticipated early pacer, Promises Fulfilled. They rounded the first turn of the mile and a quarter together through rain so persistent it soaked the 157,813 in attendance and bordered upon grotesque, and they got to the backstretch before Justify commenced making sure the race would be about him — one way or another. Baffert cringed at that opening 22: “Wow.” He felt relieved at seeing a 46 for the next fraction until his wife, Jill, corrected him to say it had been 45.

“ ‘I think they slowed it down,’ ” he recalled telling her. “She said, ‘No, that’s 45 and change.’ That’s not good. And after that I was just like, ‘Wow, this poor little horse, he’s going to lay down. There’s no way. He’s going to lay down.’ Man, I’ve been fretting all week, trying to get this big horse there. I mean, it’s like having LeBron James on your team. If you have LeBron, you’d better win a championship with him.”

In a field Baffert called loaded with quality and the “toughest bunch I’ve ever been involved with,” almost nobody came for Justify, save for Good Magic and Audible for peeks in the stretch. Perhaps the biggest mystery and curiosity in a race full of them, the second choice Mendelssohn wound up last. It was all heady business given that the 2017 Breeders’ Cup had passed and the new year had dawned and gotten going and then gone on a good while before Justify even raced.

He began Feb. 18, then followed March 11 and April 7, all at Santa Anita and the third one in the Santa Anita Derby, a three-length smash against the strong Bolt d’Oro. In those three races, he had beaten a combined 14 horses. For that maiden race in February, he won by 9½ lengths, and Baffert said, “I thought the timer was wrong.” Of particular note might have been that race March 11, when he ran in the mud and seemed to relish it. Come Saturday, with its three inches of deluge and its muddled 2:04.20 winner’s time, he would race against five more horses than he had in his entire career, yet he and those around him would relish it even more.

Justify’s ownership group fairly crowded the interview dais Saturday evening. One of the bunch — former trainer Elliott Walden, who runs WinStar Farm — had to request an extra chair. The mass included the operations China Horse Club, Head of Plains Partners, Starlight Racing and WinStar Farm, and the mass also owns Audible. The group included even the prime minister of Saint Lucia, Allen Chastanet, seated next to Teo Ah Khing of China Horse Club, whose group has begun a horse racing project in that Caribbean country.

“I’m just along for the ride,” said Starlight Racing’s Jack Wolf, the first Louisvillian to own a Derby winner in 104 years.

“I saw the way [Baffert] looked at the horse [early on] and the way he was acting around the barn,” said Solomon Kumin of Head of Plains Partners. “I came back and said, ‘This has got to be the real deal.’ ”

“Thank you, America,” said Teo, a Malaysian-born Harvard graduate and architect. “The win today is the equivalent to a gold medal in the Olympics for the China Horse Club and for the Chinese.”

All the eight men in the row of winners, counting Baffert and Smith, did fret to various degrees as to the meaning of the appalling weather. Baffert found solace in Justify’s coolness in the paddock. Smith entered the gates having won one of his first 23 Derby entries, aboard absurd long shot Giacomo in 2005, and having finished an aching second in 2012 aboard Baffert’s beloved Bodemeister.

“I knew if I could get him out of there, just get him into a big rhythm,” Smith said, “I mean, he can go fast, because that’s how good he is.” Into the clear, Smith sighed relief. He thought, “ ‘You do it from here, man.’ I basically just stayed out of the way and just kept a leg on each side and my mind in the middle.”

After the 45, Smith let Justify get some air. Asking Justify again toward the far turn, Smith found a willing teammate. He had been “losing sleep, in a good way” ever since Baffert put him on Justify for his second race, and now his daydream was coming true. “Going 45 and still finishing like he did was just incredible,” Smith said.

“Not only that,” Baffert stopped himself at one point, “he’s the most beautiful horse. He is a specimen of a horse. . . . He has that presence about him. That’s one thing about every day at Santa Anita, everybody says, ‘Who’s that?’ And that’s the only one I know for sure who it is.”

Chuck CulpepperChuck Culpepper covers national college sports, as well as some tennis, some golf and some international sports for The Washington Post. He has written previously for Sports On Earth at USA Today, the National (Abu Dhabi), the Los Angeles Times, Newsday, the Oregonian and, beginning at age 14, the Suffolk Sun of the Virginian-Pilot. Follow